I also prefer the Instant Action. The new glade one leaves a funky odor once the cat urine starts mixing with it. This has been the best to neutralize all odors. Take it from an OCD freak. I can't smell a thing with this brand.

I prefer the Instant Action classic scent because it is effective in controlling litter box odors. Tidy Cats used to make a Small Spaces Instant Action litter that had a green label, and smelled vaguely of apples ( I loved that litter, it controlled odors like no body's business). If you can find that specific product, I would recommend that litter over the others. But the classic Blue label has been great as well.